Alarming predictions that global warming could cause sea levels to rise 6ft in the next century are wrong, it has emerged.

The forecast made by the influential 2007 Intergovernmental Panel on Climate Change, which would have seen cities around the world submerged by water, now looks ‘unlikely’.

A Met Office study also rules out the shutdown of the Atlantic Ocean’s conveyor belt, which would trigger Arctic winters in Britain like those seen in the film The Day After Tomorrow.

Okay, before I point out everything else that’s wrong with this: The Day After Tomorrow is about as accurate a depiction of climate change as The Matrix is of computer programming. Regardless of what the climate does, we won’t actually have entire cities buried under frozen tsunamis, roamed by packs of wolves.

So, was the IPCC wrong? In their AR4 report (the one in question here) they said that over the 21st century, sea levels will rise by between 18 cm and 58 cm. In Daily Mail terms, that’s between 7 inches and about 2 feet (p. 45, which is p. 23 of the pdf, annoyingly). A 2 foot rise this century is rather a lot less than a 6 foot rise this century. Where did this error come from?

According to the report, beyond 2100, sea levels could rise higher – the theoretical maximum looks to be something between 7 and 10 metres – but that’s not what the Met Office study, “Summary of Post-IPCC AR4 work“, is about.

The Met Office says:

The relationship between temperature and sea-level rise is non-linear and the range for 21st century sea-level rise remains uncertain.

Some evidence that sea-level rise by 2100 may exceed the 95th percentile AR4 model-based projection of 59 cm.

Evidence that a rise significantly above 2 m by 2100 is very unlikely.

Median projections for 2100 under ‘business as usual’ scenario: AR4 model range of sea-level rise for this scenario was 0.21–0.59 cm. However, some of the newer evidence suggests that a sea-level rise of 2 m cannot be ruled out, but an increase of more than 1 m is currently viewed as unlikely.

So in fact, the Met Office says that the IPCC may have underestimated sea level rises, not overestimated them.

The Met Office never called the IPCC “alarmist”, they never said the IPCC “was wrong”, and even if the upper limit of an IPCC estimate had been rounded down, that wouldn’t make it wrong. It would just mean that we were to able to put more accurate upper bounds on sea level rise. This is all quite clear in the Met Office study; surely “Daily Mail Reporter” has to have read this report – and the IPCC report – to write this story. There’s no way such a massive error could have crept into this story.

The Mail accuses the IPCC of being alarmist and wrong. Perhaps they should look in the mirror first.